1. Field of the Invention
The present invention relates to a disc recording and/or reproducing apparatus and an optical pickup apparatus, particularly relates to a disc recording and/or reproducing apparatus and an optical pickup apparatus provided with constitution for preventing an objective lens from being contaminated.
2. Background of the Invention
For example, in equipment (hereinafter, called an optical disc drive) for reading information recorded on an optical disc or recording information on an optical disc by radiating a laser beam on an optical disc of a compact disc (CD) player and others, an optical pickup apparatus provided with various optical components such as an objective lens, a beam splitter and a laser diode is used.
In the above optical pickup apparatus, the positional relationship among each optical component and optical characteristics are strictly adjusted so that a laser beam is a beam spot with desired size and irradiates the recording surface of an optical disc.
In an optical disc drive using the above optical pickup apparatus, a malfunction caused by the optical pickup apparatus occurs very frequently. That is, as information cannot be reproduced or recorded from/on an optical disc and an error occurs in reading information required for controlling the relative position of an optical pickup apparatus to an optical disc because dust and others which get into an optical disc drive adhere on the surface of an optical component such as an objective lens of an optical pickup apparatus and these deteriorate the optical characteristics of the optical component, most of such malfunctions are caused.
Therefore, to prevent such a malfunction, there is a method of preventing dust and others from adhering on an optical pickup apparatus or a method of constituting so that dust and others are difficult to adhere on an optical pickup apparatus by sealing an optical disc drive as much as possible to prevent dust and others from getting into the optical disc drive from outside. The above method may be used for equipment constituted by only an optical disc drive, however, some equipment in which an optical disc drive and another device are combined cannot be sealed because of heat release and the above method is not general.
There is also a method of covering optical components when an optical pickup apparatus is not used, for example when an optical pickup apparatus is moved outside the outermost position of an optical disc. However, in the above method, a drive mechanism and others for opening and closing a cover are required to be all newly designed, the cost is increased and the realization is difficult because a drive mechanism for opening and closing the above cover is required to be added and distance in which an optical pickup apparatus is moved is extended.